Detection of heterogeneous vancomycin intermediate resistance in MRSA isolates from Latin America
Journal
Journal of Antimicrobial Chemotherapy
ISSN
0305-7453
1460-2091
Date Issued
2020
Author(s)
Betsy E Castro
Maritza Berrio
Monica L Vargas
Lina P Carvajal
Lina V Millan
Rafael Rios
Angie K Hernandez
Sandra Rincon
Paola Cubides
Erika Forero
An Dinh
Carlos Seas
Cesar A Arias
Jinnethe Reyes
Lorena Diaz
Type
Resource Types::text::journal::journal article
URL Institutional Repository
Abstract
<jats:title>Abstract</jats:title><jats:sec><jats:title>Background</jats:title><jats:p>Vancomycin is a common first-line option for MRSA infections. The heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) phenotype is associated with therapeutic failure. However, hVISA isolates are usually reported as vancomycin susceptible by routine susceptibility testing procedures.</jats:p></jats:sec><jats:sec><jats:title>Objectives</jats:title><jats:p>To detect and characterize the hVISA phenotype in MRSA isolates causing infections in nine Latin American countries.</jats:p></jats:sec><jats:sec><jats:title>Methods</jats:title><jats:p>We evaluated a total of 1189 vancomycin-susceptible MRSA isolates recovered during 2006–08 and 2011–14. After an initial screening of hVISA using glycopeptide-supplemented agar strategies, the detection of hVISA was performed by Etest (GRD) and Macro-method (MET). Isolates deemed to be hVISA were subjected to population analysis profile/AUC (PAP/AUC) and WGS for further characterization. Finally, we interrogated alterations in predicted proteins associated with the development of the VISA phenotype in both hVISA and vancomycin-susceptible S. aureus (VSSA) genomes.</jats:p></jats:sec><jats:sec><jats:title>Results</jats:title><jats:p>A total of 39 MRSA isolates (3.3%) were classified as hVISA (1.4% and 5.6% in MRSA recovered from 2006–08 and 2011–14, respectively). Most of the hVISA strains (95%) belonged to clonal complex (CC) 5. Only 6/39 hVISA isolates were categorized as hVISA by PAP/AUC, with 6 other isolates close (0.87–0.89) to the cut-off (0.9). The majority of the 39 hVISA isolates exhibited the Leu-14→Ile (90%) and VraT Glu-156→Gly (90%) amino acid substitutions in WalK. Additionally, we identified 10 substitutions present only in hVISA isolates, involving WalK, VraS, RpoB and RpoC proteins.</jats:p></jats:sec><jats:sec><jats:title>Conclusions</jats:title><jats:p>The hVISA phenotype exhibits low frequency in Latin America. Amino acid substitutions in proteins involved in cell envelope homeostasis and RNA synthesis were commonly identified. Our results suggest that Etest-based methods are an important alternative for the detection of hVISA clinical isolates.</jats:p></jats:sec>
Cite this document
Castro, B. E., Berrio, M., Vargas, M. L., Carvajal, L. P., Millan, L. V., Rios, R., Hernandez, A. K., Rincon, S., Cubides, P., Forero, E., Dinh, A., Seas, C., Munita, J. M., Arias, C. A., Reyes, J., & Diaz, L. (2020). Detection of heterogeneous vancomycin intermediate resistance in MRSA isolates from Latin America. Journal of Antimicrobial Chemotherapy, 75(9), 2424-2431. https://doi.org/10.1093/jac/dkaa221
Subjects
anti-bacterial agents
;
humans
;
latin america
;
methicillin-resistant staphylococcus aureus
;
microbial sensitivity tests
;
staphylococcal infections
;
staphylococcus aureus
;
vancomycin
;
bacterial protein
;
chloramphenicol
;
ciprofloxacin
;
clindamycin
;
cotrimoxazole
;
daptomycin
;
erythromycin
;
gentamicin
;
lincosamide
;
linezolid
;
macrolide
;
mikamycin b
;
minocycline
;
rifampicin
;
teicoplanin
;
tetracycline
;
vancomycin
;
antiinfective agent
;
vancomycin
;
amino acid substitution
;
antibiotic resistance
;
antibiotic resistome
;
antibiotic sensitivity
;
argentina
;
article
;
bacterial genome
;
bacterium detection
;
bacterium identification
;
bacterium isolate
;
brazil
;
chile
;
clonal species
;
colombia
;
computer model
;
controlled study
;
ecuador
;
epsilometer test
;
evaluation study
;
genetic procedures
;
guatemala
;
heterogeneous vancomycin intermediate staphylococcus aureus
;
macro method
;
methicillin resistant staphylococcus aureus
;
mexico
;
nonhuman
;
peru
;
phenotype
;
phylogeny
;
population analysis profile method
;
staphylococcus aureus
;
vancomycin resistance
;
vancomycin susceptible staphylococcus aureus
;
venezuela
;
whole genome sequencing
;
genetics
;
human
;
microbial sensitivity test
;
south and central america
;
staphylococcus aureus
;
staphylococcus infection